Self-locking screwing attachment devices for securing at least two parts to each other, having generally the form of a nut screwed onto a threaded tip, provided with reinforced releasable coupling means, for preventing said at least two parts from being importunately unscrewed, are known. This reinforced coupling means performs a self-locking of the coupling when screwing the nut on the tip.
These known devices generally have drawbacks of several kinds:                the device consists of several separable parts which can be lost and should be assembled according to an accurate order,        nut of such device is not adapted to parts to be assembled and/or to threaded tips having multiple shapes and is not necessarily standard; the friction surfaces required for the clamping are highly dependent on the shape of parts to be assembled, resulting in an uncertain clamping efficiency according to configurations; the adaption of these known nuts sometimes requires a significant and extensive machining,        poorly optimized dimensions.        